Bark is the outmost layer of
stems[?] and
roots of
woody plants (
trees). It consists of three layers: the
cork, the
phloem, and the
vascular cambium - in other words, most of the stem except for the
xylem. (This division may seem arbitrary, but the easiest way to split a stem parallel to its length is by pulling the bark away from the xylem.)
The vascular cambium is the only part of a woody stem where cell division occurs. It contains undifferentiated cells that divide rapidly to produce secondary xylem[?] to the inside and secondary phloem[?] to the outside.
Along with the xylem, the phloem is one of the two tissues inside a plant that are involved with fluid transport. Phloem's specific job is the transport of organic molecules - particularly sugars - to wherever they are needed.
Cork, sometimes confused with bark in colloquial speech, is the outermost layer of a woody stem, derived from the cork cambium. It serves as protection against damage, parasites and diseases, as well as dehydration and extreme temperatures.
Cork can contain antiseptics like tannins. Some may also include cork (material) for further insulation, giving the bark a chatacteristic structure.
Among the commercial products bade from bark are cinnamon and quinine.
Bark is also the word used to describe the characteristic sound made by certain animals, such as
dogs,
foxes, or
sea lions.
To
bark describes a rude way of talking.
A
bark is a specific
sail-plan of sailing ships, sometimes used poetically to describe boats of any kind.
For other meanings, see
Jesuit's bark[?],
bark cloth[?],
barque.
- See also : Bark painting[?], Bark beetle[?]
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